We report a case of a 13 year old male patient, well nourished, from Iquitos city with signs of dengue fever who also fulfills definitive criteria for dengue hemorrhagic fever. Classification of the gravity was degree II.Diagnosis was confirmed by serologic studies, showing serotype 3. This could be the first case of dengue hemorrhagic fever at the Hospital Regional de Loreto, although it is probable that in the past there might have been cases that could not be suitably documented. (Rev Med Hered 2008;19:).